Car radio problem

At full volume, front speakers are barely audible. Rear speakers are at a reduced volume. Have checked fuses, all seem OK. I am not getting a LOCKED message. Did recently have to jump start as H/L were left on. Any help would be appreciated.

What year?If it is 2001 and up,go to the dealer and it has to be programed with the Tech 2.The old way will not work on them.

Make sure your pos/neg speaker wires are correct, this goes for any year or any vehicle. Easy mistake to make, it could happen to anyone. Just somethin to check, I'm sure you got it by now though